The present invention relates to an adapter for securing the power and fluid carrying cables in a TIG (tungsten inert gas) welding assembly to the output stud on the welding machine (power supply). Welding machines take conventional AC current of high voltage/low amperes and convert the current to welding currents which are typically high amperage/low voltage. The machine allows regulation of the output current to suit the welding requirement. Typically the machine has two output terminals which are usually 0.5 inch diameter metal studs. The electrical leads (welding cables) are attached to these output studs in accordance with the particular machine. The electrode cable is attached to one of the studs and the ground cable to the other. In the case of TIG welding, the TIG torch power cable must be connected to one output stud using an adapter called a power cable adapter. The adapter is constructed of an electrically conductive material, preferably copper or brass, and is provided with a conduit portion extending therethrough having the proper threaded connections at its inlet and outlet ends for attachment of the TIG torch power cable carrying line and either the shield gas supply line in the case of air cooled TIG torches or the water return line in the case of water cooled TIG torches. The adapter is typically secured to and electrically coupled with the output stud by means of an upstanding ear portion on the adapter that has an aperture therein sized to receive the output stud. A large fastening nut threadably engages the stud about the ear portion of the adapter to secure the adapter on the output stud.
Power cable adapters have been machined from brass forgings or from machine components soldered together and configured such that the TIG torch power cable and fluid supply hose are attached at the inlet and outlet ends of the adapter along the same center line. The welding machines for which these adapters were developed were relatively large and there was ample room for such adapters and their straight-through design. In recent years, however, the physical size of these welding machines has been substantially reduced and it has become increasingly difficult to utilize existing power cable adapters with the smaller machines due to the lack of available space near the adapter to accommodate the extending lines. As a result, the lines must be bent at relatively sharp angles proximate the adapter connections to avoid obstructions which weakens the lines. In addition, the torch lines also carry fluid. The power cable in an air cooled TIG torch assembly has a surrounding hose which carries the shielding gas from the outlet end of the conduit portion of the adapter to the torch head. The gas is supplied to the adapter by a gas supply line. In water cooled TIG torch assemblies the power cable is again provided with a surrounding hose which carries the cooling water back from the torch head to the water return line through the adapter. Thus, the two lines connected to the adapter are in fluid communication through the adapter and when one or both of these lines are sharply bent, they can crimp, restricting the fluid flow therethrough and adversely affecting the operation of the welding apparatus.
In view of the increasing trend toward smaller welding machines in TIG torch welding, there is an increasing need for a power cable adapter which can electrically couple the power cable to the output stud of a welding machine and secure the power cable carrying line and the associated fluid supply line in fluid communication such that tight crimping turns in the lines are avoided irrespective of the size and design configuration of the welding machine. The power cable adapter of the present invention satisfies this need.
Briefly, the power cable adapter of the present invention is comprised of a pair of clam shell type clamp members formed of an electrically conductive material and configured such that upon being disposed in a substantially adjacent juxtaposition, the clamp members define a channel extending laterally therethrough and a circular aperture, the central axis of which is perpendicular to the central axis of the channel. The channel receives and secures between the two clamp members portions of an electrically conductive fitting tube that is preferably U-shaped and provided with connector fittings at its extended ends for attachment to the welding torch power cable carrying line and the associated fluid (gas or water) supply line. The aperture formed by the two clamp members is sized so as to receive the threaded power output stud on the welding machine such that the two clamp members can be secured together in substantially adjacent juxtaposition on the output stud about the conductive tube by a threaded fastening member. The conductive tube is thus tightly held in place within the lateral channel between the clamp members, creating a physical securement of the tube and an electrical connection between the tube and the power output stud. Upon securing the power cable carrying line to one of the threaded tube fittings, the power cable is electrically coupled to the output stud and upon securing the associated fluid carrying line to the other tube fitting, that line is secured in fluid communication with the power cable carrying line through the fitting tube.
The use of the U-shaped fitting tube in combination with the clam shell type clamp members allows the power cable carrying line and the associated fluid supply line to extend to and from the adapter in a parallel orientation and at any desired angular orientation from the welding machine. As a result, the need for the fluid carrying lines to negotiate relatively sharp turns to accommodate compact welding machine designs is substantially reduced and fluid can flow through the adapter and associated torch lines with minimal restriction. In addition, the clamp configuration of the present invention is not only economical to manufacture and easy to use, it readily accommodates fitting tubes of different configurations to accommodate further variations in machine designs thereby providing an economic and highly versatile power cable adapter for TIG torch applications.
It is the principal object of the present invention to provide an improved power cable adapter for use on a welding machine in a TIG torch assembly that accommodates a wide variety of welding machine configurations and sizes without having to induce sharp bends in either of the fluid carrying lines.
It is another object of the present invention to provide a highly versatile power cable adapter for use with TIG torch assemblies that is of simple construction and economical to manufacture.